Device for recovering condensation waters



April 3, 1934. M. SAINTE-MARTINE 1,953,491

DEVICE FOR RECOVERING CONDENSATION WATERS Filed Jan. 17. 1929 3 Sheets-Sheet 1 W44 TEE OF C 04 05/1494 TIO/V April 3, 1934. M. SAINTE-MARTINE DEVICE FOR RECOVERING CONDENSATION WATERS 3 Sheets-Sheet 2 Filed Jan. 17, 1929 EXHAIIJTJTIAM REJECT'G LII/U105 April 3, 1934. M. SAlNTE-MARTINE DEVICE FOR RECOVERING CONDENSATION WATERS Filed Jan. 17, 1929 3 Sheets-Sheet 3 Patented Apr. 3, 1934 use srrss ATE' 1T QFFICE DEVECE FQR RECOVERIN-G COND'ENSATION VJA'IERS Marius S'ainte-Martine, Grand Quevilly, France,

assignor to France Papeteries Anumyme,v Lyon, France,

Navarre, Socit a corporation of 43 Claims.

The present invention relates to an improved method of, and means for, automatically difierentiating between solutions of different conductivities for predetermined purposes, and more particularly to a novel arrangement for selectively recovering from Waste water, such water as may be safely employed in steam generators.

One of the main objects of the present invention is to provide a method of, and means for, conducting a liquid along a predetermined path, wherein a conductivity measuring circuit is utilized to continuously determine the conductivity of the liquid flowing through said path, and additional means employed for diverting the liquid into a difi'erent path whenever the conductivity of the liquid in the first path changes in a predetermined manner.

Another important object of the present invention is to provide an arrangement for selectively recovering water fit for steam generation from any water which has to be controlled by utilizing the varying electrical conductivity of the water, the arrangement comprising servomotors using a liquid under pressure, such as oil in actuating lines, and electromagnetic devices for controlling the actions of the servomotors, the arrangement insuring continuous, automatic and economical operation.

Another object of the invention is to provide a device for recovering water fit for steam generation from condensates, the device including a member for measuring the condensates, recovered waters, and rejected waters, the measuring being obtained by filling a container to a constant volume, the operations of an automatic condensate control valve and rejecting valve being registered by the valves themselves.

Another object of the invention is to provide a recovery system for waste waters wherein the latter are continuously and automatically tested to determine the fitness thereof for steam generation, a fluid under pressure, such as steam from a boiler being utilized to facilitate transfer of fit water into the boiler, as at present disclosed, and means being employed to automatically stop the feed of steam from said boiler when waste water is to be rejected.

And still other objects of the present invention are to improve generally the efliciency of devices of the type described heretofore, and to particularly provide drain water recovery apparatus which is not only durable and reliable in operation, but economically installed in a plant for the utilization of drain waters for steam production.

The novel features which are believed to be characteristic of this invention are set forth in particularity in the appended claims, the invention itself however, as to both its organization and method of operation will best be understood by reference to the following description taken in connection with the drawings in which there is indicated diagrammatically one arrangement, including circuit organization, whereby this iiivention may be carried into eiiect.

In the drawings:

Figs. 1a and 1b are partial diagrammatic views in which some of the structure is shown in section. These two views are taken mutually continuous to show the complete structure.

Fig. 2 is a detail View, partly in section, of one of the servomotors,

Fig. 3 is a view similar to Fig. 2 of the remaining servomotor.

Referring now to the accompanying drawings, wherein like characters of reference in the different figures represent the same elements, there is shown as an example a container D provided in its interior with a plurality of steam coils D, the steam inlets of the coils being conventionally represented. The container D. is provided with an outlet 0, at its base, for any material to be treated by the steam coils. The outlets of the coils D are conventionally represented by the symbol D". As stated heretofore, it is one of the main objects of this invention to provide a device which can automatically and continuously feed the output from the coils D to a steam generator, and simultaneously insure the latter against injury from such liquids eject-ed from D" which may be harmful to the generator for any reason.

For example, where the container D functions as a cellulose digestor, calcium bisulphite being employed as the digesting agent, it may happen that the coils D in the digestor corrode and leak. Obviously in such cases the liquid ejected at D" will be contaminated with chemical materials injurious to the steam generator. Clearly the device feeding the liquids from D" to the steam generator water intake must, then, be capable of differentiating between fit and unfit liquids, and additionally must be adapted to reject liquids unfit for steam production.

Such a device will now be described, it being clearly understood that the object is to direct liquids fit for steam production from the points D to the inlet 45 of the boiler 45, liquids unfit for steam generation being rejected and directed into a waste liquid container 46. The boiler 45 is, of course, shown highly conventionalized, it

being understood that the water tubes lead from the upper boiler chamber A to the lower chamber B. The remaining construction of the boiler is too well known to those skilled in the prior art to merit further explanation.

The differentiating or control mechanism essentially comprises a relay tank or vessel. The tank is made up of a hollow cylindrical member 1, and removable top and bottom closures 5, 6. A portion of the cylinder 1 adjacent the closure 6 is provided with an enlarged aperture 1, a plug 2, preferably of insulating material, being removably secured in any well known manner to the cylinder 1 so as to completely close the aperture. A pair of control electrodes 3, 4 are aiflxed to the plug 2 in such a manner that the enlarged heads of the electrodes are spaced within the cylinder interior for relative movement, the shanks carried by said plug, being movable for disposing said electrodes in closer or more distant relation to regulate the sensitivity of the electrical circuit. The restricted terminals of the electrodes extend through the plug to the exterior of the cylinder, serving as contacts for a pair of con ductors 3', 4.

Of course the plug 2 is preferably made of a material capable of resisting the chemical materials which may be in solution in the liquid in the relay tank and the latter may also be constructed of like material. Furthermore, the electrodes 3, 4 may be arranged so that the heads thereof are disposed in the same plane or in different planes. The bottom closure 6 is provided with a central opening 9, functioning as an inlet to the relay tank from the elbow passage 9'.

A jet baiile or deflector 7 is disposed over the opening 9. The deflector carries a guide member 7a for guiding the lower end of a tubular rod 19. A float 8 is arranged for sliding movement on the rod 19. The deflector 7 also serves to protect the float 8 from the force of the liquid spouting through the opening 9.

In order to supply pressure upon the liquid in the relay tank, to permit liquid to flow from it, steam or fluid under pressure is injected into the upper portion of the tank. This is accomplished through pipes 10, 11. It will be observed that the pipe 11 serves as the connecting line between the boiler chamber A and a port 11' of the steam cylinder 11a. The pipe 10 serves as a connecting line between the interior of the relay tank and another port 10 in the cylinder 11a. As will be explained in further detail, the line 19 functions as a steam inlet line to the relay tank at certain times, and as a steam outlet line from the tank at other times.

Within the cylinder 11a below the cap 11c there is disposed a piston 11b. The piston is mounted upon one end of a vertical piston rod 110 and is adapted to reciprocate within the cylinder 11a. The construction of the steam valve 11a need not be described in further detail since those skilled in the art well know how to construct a steam valve of this type. It is only believed necessary to point out that a third port 11g is provided in the top closure of the cylinder 11c, and a pipe line connected between this port and a container 10" for receiving exhaust steam.

Again the pipe line 11 is shown as broken between points X, Y to indicate that the line 11 may be long enough to permit the disposition of the inlet 45 below the level of outlet i541. Obviously, those skilled in the prior art will know how to arrange the differentiating apparatus with respect to the boiler so that liquids flow from 45a into the chamber A under the force of gravity.

The lower end of the piston rod is pivotally connected as at 12 to the intermediate part of a lateral cross beam 12. The ends of the beam 12 are pivotally connected as at 13, 14 to the vertical piston rods 15, 16. The latter, as will be more fully explained later, are elements of the servoinotors 1'7, 18.

As already stated, the vertical rod 19 is ar ranged to permit the float 8 to reciprocate along its length. Two stops 20, 21 are provided on the rod 19 to limit the movement of the float. The upper stop 21 is anixed at the end of rod 19, while the lower stop 20 is spaced a relatively short dis tance from the opposite end or" a rod 19. The upper end of the latter is, furthermore, pivoted as at 22, to a rocker arm 23. The latter is fulcrumed as at 23, at a point approximately intermediate thereof. A portion of the cylinder 1 is extended as at 1a, to house the fulcrum point 23, a portion of the rocker arm extending exteriorly of the relay tank.

A vertically movable circuit closing contact 2 has its lower end pivoted to the external end of the rocker arm 23 as at 24a. The contact is provided with a tapered head 24'. The latter is arranged for engagement with terminals 38, 39, that is, when the float 8 moves upwards against the stop 21, the arm 23 is rocked so as to move the tappet contact 24 downwards, thereby causing the head 24 to engage the terminals 88, 39. The tappet lever 2 5 functions as a quick make and break switch for short circuiting a circuit which in eludes the solenoid winding 36, the terminals 38, 39 being connected to the terminals of the winding 36' through conductors 38, 39.

External of the relay tank the vertical piston rod 15, of the servomotor device 17, is provided at its lower end with a double faced head 25. headed portion of th rod is arranged for vertical reciprocation within a conventional type of valve body Z. The ipe line (not shown) between the outlets D" and the relay tank, feeds directly into the inlet opening 43. It should be clear that those skilled in the art will arrange the outlet: T3 in such a manner, with respect to the relay tank inlet 43, that gravity flow can be taken advantage of. The valve body Z is provided with a pair of passages 25, 25".

A central port 25a is provided, and functions to connect inlet 43, upper passage 25 and lower sage 25" to passage 9', when the lower face of head 25 is seated in port 252). When the piston rod 15 moves upwards, the upper face of head 25 is seated in the port 25a, with the result that liquid cannot flow from the inlet 43 to the passage 9'. With the 25 in the last named position,

the lower elbow passage 9" is connected with the upper elbow passage 9. If the head 29 of piston rod 16 is seated in the upper port of the opposite valve body Z, then the passage 25" of the latter will connect with the outlet passage 45a.

Should the rod head. 29 be seated port 25?) of the outlet valve body Z, then the passage 9 would feed its liquid through passages 25 and 46, into the rejected liquid container 46. It will therefore be seen that the two valve bodies Z, Z are exactly the same in construction. The upper portion of each valve body Z is of well known design, the left valve body having the construction of its upper portion shown in more detail than the opposite one. However, it is believed that sufficient has been said about these valve bodies to instruct those skilled in the art how to adapt them to this invention.

The piston rod 15 of the servomotor 1'7 functions to regulate the filling and exhausting of the relay tank. A pair of springs 26, 27 are provided between fixed stop plates 26a, 27a. The upper spring 26 is disposed between the plate 26a and a movable collar 28a, while the lower spring 2'? is disposed between the collar and the lower fixed stop 27a. ihe rod 15 passes through the center of the plates 27a, 26a, the collar 28a being rigidly affixed to the rod 15 for movement therewith. The stop plates 26a, 27a are rigidly affixed to the parallel, spaced rods 26 depending from the casing of the servomotor 17.

The springs 26, 27 are opposed in action and function to set the rod head in an intermediate position, leaving both ports 25a and 251) open, upon failure of oil pressure in the servomotor, or current in the control circuit. When both ports 25a and 251) are open, liquid readily flows from passages 43 and 9 through passage 9" for further disposition by the remaining valve body.

lhe servomotors 17 and 18 are similar in many respects. However, the latter differs in that it is provided with but a single spring 28 between a fixed stop plate 16, the latter being centrally apertured to permit the rod 16 to slide therethrough, and a collar 28' secured to the rod 16 for movement therewith. The collar 28 is centrally apertured to receive the rod 16 therethrough, while the stop plate 16' is affixed to the spaced rods 26" depending from the casing of servomotor 18.

The spring 28 functions to lower the rod head 29, should servomotor oil pressure or control circuit current become inadequate, thereby causing the liquid to flow through passages 25', 46 into the waste container 46.

In order to provide visual indications and registration of the operation of the functioning of the valves Z, 2. each collar has affixed to it an index pointer 30. The head of each pointer is adapted to move over the face of a scale 30, the latter being provided with conventional indicia 31, but said indicia may include indicating words, not shown, such as, for the valve 25 fillingemptying and, for the valve 29 badgood. Thus, each pointer and scale can function as a register. It is obvious that instead of directly attaching the regi ters to the rods, telemetric methods, well known in the art, may be employed to register at a remote point.

A ain, as supplementary to the registers, electric signal lamps may be provided to flash a signal when each pointer attains a predetermined point. Thus, the power line C may have conductors 32 leading from it to spaced terminals, the lamp 32 being disposed in one of said conductors, while the conductor 33 may be arranged between the power line C and a pair of space terminals. Each pointer 30 may have a contact member extending therefrom, each member terminating in a tapered head 32a, whereby movemerit of a pointer to a predetermined point r sults in closin of the lamp circuit and flashing of a signal. If desired, a pilot lamp 34 may be connected across the line C to warn the operator of current deficiency, or failure. It is clear that the registers, signal lamps and pilot may be assembled on a single board adjacent or remote from the relay tank.

The oil feeding circuit for the servoinotors 17, 18 will now be described. An oil pump 35 of conventional design is utilized for moving the oil through the pipe lines. A motor 33a (shown only in diagrammatical manner) is energized from the lines 0, through conductors 3%, the motor being mechanically coupled to the oil pump gears in any desired fashion. The motor drives the gears thereby elevating the oil from the tank 500 into the pipe line 50' (the line 50' branching off from the line 50) to the valve chests 17a, 18a of the servomotors 17, 18.

This construction is more clearly shown in Figs. 2 and 3, wherein it is disclosed how pipes 50, 50 feed into their respective chests 17a, 18a. The oil is returned to the tank 59c, from each chest through return pipes to a common return line 50d, pipe 50a, returning the oil from chest 17a, pipe 50c, returning the oil from chest 18a. Thus, referring to Fig. 2 it will be seen that pipe line 50a taps into the bottom of the outwardly extending housing 52. The same construction is true of the chest 18a and its associated pipe line 502. It will therefore be seen that a closed oil circuit is provided between the oil pump 35 and both servomotors. A safety valve 51 is provided to permit adjustment of the oil pressure to whatever value desired.

Referring now to the el ctrical circuits ernployed in the present invention, it is first pointed out that while uni-directional current may be employed over the lines C, it is preferred to use alternating current in order to avoid the electrolysis of liquid in the relay tank.

The servomotor 1'? includes an electromagnetic device 36 for actuating the slide valve lever 52. This device 36 preferably comprises a winding 36" and an armature 36a embraced by said wind- The lever 52 is pivoted at one end thereof, as at 52", to the lower end of the armature 36a. One terminal of the winding 36 is connected in series with the resistor 42 to one of the lines C, while the other termmal of the Wind ng is connected to one of the lines C through a conduct-or 38b. The resistor 42 functions to regulate the field strength of the winding 36'. Obviously long as a normal flow of current is had through the circuit including the resistor 42 and winding 36, the armature 36a is maintained in maximum attracted and upward position. However, as soon as the winding 36 is short circuits-d, by the tappet head 24 contacting with the terminals 38, 39, the field strength of the winding 36' is greatly reduced. As a result of the reduction, the attraction f the armature 36a decreases, and the armature moves downwards thereby actuating the lever 52.

The servomotor 18 also comprises an electromagnetic device 37 consisting of a winding 37 connected through a conductor 40' to one terminal of a rheostat resistor ll, the winding being connected to the movable contact 41' of the rheostat through a conductor 41a. The conductor 40 is tapped at an intermediate point, and is connected to one of the lines C through a fixed resistor 40. The conductor 41a is similarly connected through a conductor 46a, to another line C. The resistor 41 is provided with a plurality of taps repr senting various adjustment positions of the contactor 41. Finally, the electrode 3 is connected through a conductor 3 to a point on conductor 49' between resistors 40 and 41, while electrode l is connected through a conductor 4', to the junction of conductor 41a and the pivoted end of contactor 41.

A vertical armature 37a is disposed within the winding 37, the lower end of the armature being pivotally connected as at 53, to a slide valve lever 53. When the contactor 41 has been adjusted to a desired tap onxthe resistor 41, a predetermined flow or current through the winding 3'? will result in attraction of the armature 37a in upward direction. Should the space between electrodes 3, l now become conductive, as for example if the space were filled with a conductive liquid, then clearly the winding 37 would be short circuited. As a result the field strength of the winding would be greatly reduced, and the armature 37a would drop thereby moving the lever 53 in a downwardly, arcuate path.

The particular equipment herein disclosed for short circuiting the windings 36 and 3'7 is illustrated in a preferred form, but other arrangements differing from those shown could be used in connection with the servomotors for bringing about the same result. The function of the rheostat s1 is to permit adjustment of the sensitivity of the servomotor 18 in actuating the rod head 29.

The mode of operation of the oil slide valves will now be more readily understood, especial reference being made to Figs. 2 and 3.

In normal operation, the windings 36, 37 of both electromagnetic devices 36, 37 will be continuously energized. Consequently, the armatures 36a, 37a will be attracted into upward position. The effects on the rods 15 and 16 however, will be different. In the case oi rod 15 upward movement of the armature 36a causes downward movement of a finger 66. The latter is housed within the valve chest 17a, and is fulcrurned at 6i angular translation with the exterior lever 52.

Within the valve chest is disposed a slide piston 62 provided with a central bore 63. The casing or cylinder 17b is provided with two oil ports 65, 66. The piston 62 is adapted to reciprocate within the valve chest 17d, and is capable of alternatively closing the ports 65, 66. By means of an abutment 67 the finger 60 is caused to move the slide valve piston 62 downwards to close the port 66 and open the port 65, whenever the armature 36a is attracted upwards.

When the port 66 is closed oil under pressure, fed into the valve chest from pipe 56, flows through port 65 and fills the interior of the cylinder 1%. Although oil flows through bore 63, it cannot flow anywhere except through port 65.

The piston rod 15 is provided with a piston 76 adapted to vertically reciprocate in the cylinder of the servomotor 17. When the oil under pressure flows through port 65, it forces the pi..- ton 70 downwards, thereby moving the rod 15 downwards. Any oil that seeps by the piston '76 is caused to flow through the passage 65 or 66 into the return pipe 50c. Clearly, when the winding 36 is short circuitecl, the armature 36a. in moving downwards causes the lever 52 to swing downwards with the result that the finger 66 swings upwards. The piston 62 is therefore caused to slide upwards, thereby closing port 65, and opening port 66. As a result the oil flows through bore 63, port 66, forces the piston '70 upwards, and results in inward motion of the rod 15. The oil would return through pipe 560; to the oil pump.

Referring to Fig. 3, it will be seen that an inverse action takes place in the case of rod 16. When the armature 37a is attracted upwards, the lever 53 swings upwards. However, due to the manner of securing the lever 53 to linger 60, as at 61., when the lever 53 swings upwards, the finger also swings upwards, and causes the valve piston 62 to slide upwards and close port 65". Oil under pressure fed into the valve chest 18 through pipe 50 flows through bore 63', open port 66, causes the piston 70 to move upwards, and results in upward motion of the rod 16.

Conversely, when the winding 37 is shortcircuited, the armature 37a, lever 53, ringer 60' and piston 62 move downwards in succession. This closes port 66, opens port 65', permits the piston 76 to be forced downwards, and thereby also the rod 16. The pipe line 56c, serves as an oil return line. Thus, it will be seen that upward motion of the armature of solenoid 36 results in a reverse movement or rod 15, while upward motion of the armature oi solenoid 37 results in a similar movement of rod 16.

Having now described the construction and arrangement or" the component parts of the invention, an explanation of the operation of the device vrill now be given. Assume that float 8 is at its lowest point, in contact with stop 20. The motor 33a is driving the oil pump 35, and the solenoid windings 36, 37' are normally energized; the latter is particularly assured for 36 since the tappet contact kept out of contact with shor circuit terminals 38, 39. As shown above the rod 15 will be forced downwards, compressing spring 2'2, thereby closing port 25b and passage 9". Rod 16 on the other hand will be urged upwards, compressing spring 23, thereby connecting passages 59 and 450;.

Suppose now that liquid is discharged through cutlets D, and that the liquid is of a low conductivity. That is to say, it is not contaminated with an electrolyte.

The condensation water flows into inlet 43, through open port 25a, passages 25", 9 and into the relay tank. Water will continue flowing into the tank until the float 8 abuts the stop 21; when the latter happens the arm 23 is rocked on fulcrum 1c, the tappet 24 pulled downwards, the circuit 38, 39, 39, 36?), C, 42, 38 close and the winding 36' short circuited. The armature 36a is thereupon released with the result that the rod 15 is moved upwards in a manner already described in great detail in connection wit Fig. 2.

Upon the rod 15 moving upwards the port 25a is closed, cutting oil the flow to the relay tank, the spring 26 being compressed. It will be seen that the outlet passage 9 of the relay tank communicates with the passage 9". The relay tank is now ready to exhaust through passages 9, 9", 25", 45a, 45 into the chamber A. Since the liquid in the space between the electrodes 4 is not conductive to a sufficient extent the winding 37 remains normally energized, with the result that the rod 16 is maintained in upward position thereby keeping port 25?) open.

The live steam in chamber A is utilized in exhausting the relay tank after short circuiting of the winding 36'. The opening and closing or the lines 10 and 11 are controlled by the piston or throttle 11b. The latter is actuated by the rods 15 and 16 through cross beam 12 in such a manner that steam can only be introduced into the relay tank when both heads 25, 29 are simultaneously in upper positions. Thus, when the winding 36' is short circuited the rod 15 is elevated, and while moving head 25 into upper position, the rod 110 is caused to move upwards, the beam 12 and rod 11c pivoting at 14.

In this upper position of the valve heads 25, 29, the piston 11b is in a position which permits the steam flowing from line 11 to flow through port 11, port lO, line 10, and into the relay tank.

tremely undesirable for some reason.

Obviously, the piston 1lb will be designed to shut off the flow to port 119, while permitting ready flow from port 11 to port 10'. It is believed that those skilled in the art will readily be able to construct a piston of this type with the present diagrammatic disclosure. The steam introduced into the relay tank functions to drive the water in the tank through passages 9', 25", 9", 45a, 45' into the chamber A, the water in the relay tank being under a load with respect to chamber A.

As the tank is emptied the float 8 descends until it abuts the stop 20. The tappet head 24 moves out of contact with terminals 38, 39, thereby permitting normal energization of winding 36. As a result, the oil pressure restores the rod 15 to its lower position, the head 25 closes port 251), and the steam throttle 11h cuts oif the flow of steam from pipe 11 to pipe line 10, and instead leaves ports 10 and 119 open with the result that the pipe 10 is connected with the exhaust line 100, thus allowing steam which had been introduced into the relay tank to escape after utilization. It will thus be seen that the filling of the relay tank is now readily accomplished since there is a free path between inlet 43 and opening 9.

Assume now, that the liquid entering the inlet 43 carries in solution some material (acid, basic or electrolyte in general) whose presence in the steam chambers A, B and water tubes 45" is ex- Clearly such material renders the liquid conductive. Therefore as such a conductive liquid flows into the tank and fills the space between the electrodes 3, 4, the circuit 3, 4, 4', 41a, a, 40, 40,

3 gradually tends to short circuit the winding 37. As soon as the electrodes have been immersed in the conductive liquid the short circuiting action on the Winding 37 will be complete With the result that the armature 37a drops.

As explained heretofore in connection with Fig. 3 the rod 16 moves downward, with the result that the head 29 closes port 251). Thus, before the float 8 has reached stop 21, the passage 9 is connected with the passages 25, 46 to discharge rejected, undesired liquids; the passage a being closed. When the float 8 abuts the stop 21, as before, it causes short circuiting of the winding 36, and closing of the port 25a by the head 25. The entire contents of the relay tank is now ready to be discharged into the tank 46.

It is to be noted that when the head 29 is in rejecting position (closing of port 25b) the introduction of steam into the relay tank is made impossible, even though the tank is being emptied. However, it should be realized that in this position of the throttle 11?), the pipe 10 and exhaust line are in communication.

Since the line 100 is open to the air the rejected liquid flows out of the relay tank into the tank 46 by gravity. When the relay tank is empty of undesired liquid the valve head 25 assumes its normal positions so as to permit flow into the relay tank.

It is believed that the aforegoing detailed description is sufficient to enable those skilled in the art to practice the invention. However, certain remarks may be of aid in practicing the invention. Whatever be the nature of the troubles during operation (oil pump or motor getting out of order, leakage of oil. circuit, inadequate oil supply, failure of control circuit current) the rod 15 of the valve head 25, actuated by the two opposed springs 26, 2'7 disposes the head 25 in an intermediate position. On the other hand the rod 16 of the valve head 29 is forced downwards by the action of the spring 28 which always tends to expand, thus opening the passage leading to the drain pipe 46, and closing the pipe line leading to the recovery outlet 45a.

The condensed waters coming from the outlets D" are in such case merely allowed to flow into the tank 46. Clearly, if the solenoid 37- were to fail or the electric circuit associated therewith fail, the valve head 29 would be forced into rejection position, while the valve head 25 would continue to function normally.

It will therefore be seen that the operation of the digestor D is not eifected by any failures as outlined above, and the boiler chambers are safe-guarded during all times that the differentiating mechanism is faulty.

Besides its use with any system for the recovof condensates, the above described arrangement is obviously useful for selecting products in chemical processes by taking advantage of their varying conductivities while in solution. By means of the present invention it is possible to differentiate between solutions of varying conductivities in a continuous automatic and safe manner.

Thus it is seen that while the herein invention is shown in connection with a source of waste water and a steam generator, the invention as claimed in the broader claims is not in the least limited to waste water or to generators, but is broad enough to cover control and selection of any suitable liquid or material from any source or for any purpose. And while the drawings show only one apparatus, the invention is not thus limited, as the apparatus may be used in series. For instance, material entering at the inlet passage 43 of a primary apparatus may be in accordance with its conductivity, discharged as two grades at the respective passages 45a, 46. Then one or more similar secondary apparatuses may receive the material from one or both respectively of the passages 45a, 46 of the primary apparatus and further separate it into grades. Additional tertiary apparatuses may receive material from some or all of the passages 45a, 46 of the secondary apparatuses, and so on, thus making it possible to separate the material into any desired number of grades. 7 While only one system has been indicated and described for carrying the invention into effect it will be apparent to one skilled in the art that the invention is by no means limited to the particular organization shown and described, but that many modifications in the apparatus, circuit arrangements, and uses, may be employed, without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. A method. of selectively differentiating between water fit for steam generation and water unfit for the purpose, consisting in conducting the water of variable conductivity through a predetermined path, utilizing the conductivity of the water flowing through the path, and diverting the water from said path to a rejection path when the conductivity varies beyond a predetermined limit.

2. A method of steam generation which consists in collecting waste water, passing said Water through a desired path for steam generation, continuously determining whether the conductivity of said water in said path varies during said passage, and automatically utilizing the conductivity for diverting said water to another path with.

predetermined variation.

3. A method of utilizing waste water for steam production which consists in collecting the waste water, establishing an electrical path through said water while collecting the latter, establishing a utilization path for the water, and conducting part of the water through said utilization path only when the flow of current through the electrical path is below a desired value.

4. A method of utilizing waste water for steam production which consists in collecting the waste water, establishing an electrical circuit through said water while collecting the latter, providing a utilization path for the water, establishing a rejection path for water unfit for steam produc tion, and conducting part of said water through said rejection path when the conductivity of the water rises to a value sufiicient to permit the flow of current through said electrical circuit.

5. In combination, a source of drain water, a collecting tank provided with a passage for conducting collected drain water therein, a steam generator, said passage connecting with said generator, spaced electrodes disposed within said tank and in contact with said collected drain water, an electrical circuit including said electrodes, means associated with said tank providing a drain water rejection passage, and electro-magnetically controlled valve means, regulated by said electrical circuit, for automatically diverting the drain water to said rejection passage when the conductivity of the collected drain water is above a predetermined value.

6. In combination with means for conducting a liquid along a desired path, and a second path, electrodes engaging said liquid, which latter is subject to changes of conductivity, an electric circuit including said electrodes, and means controlled by the circuit responsive to said changes for automatically diverting the liquid to said second path.

7. In combination, a source of liquid to be controlled, a collecting tank, an intermediate tank, means for feeding liquid of variable conductivity from said source into the intermediate tank, means for controlling the flow of liquid from said intermediate tank to said collecting tank, said last means comprising a valve device normally maintained in position to permit flow to the collecting tank, an electric circuit having electrodes in the liquid of said intermediate tank, and means operable by said circuit ior positioning said device to obstruct said flow when the conductivity of said liquid increases to a predetermined value.

8. In combination with a source of condensed steam and a relay tank, means for conducting said condensed steam to said tank, a steam generator, means forming an exit passage from the relay tank, and a connecting passage connecting said tank with said generator, spaced electrodes in contact with said condensed steam, an electrical circuit including said electrodes, and means controlled by the circuit for automatically causing the liquid to discharge through the connecting passage or the exit passage.

9. In combination, a main passage for conducting liquid and communicating with a branch passage; means for testing the quality of the liquid in the main passage; and means associated with said passage and controlled by said testing means for at times automatically in accordance with the test diverting liquid from the main passage to the branch passage.

10. In combination, a vapor generator; means providing a passage for conducting liquid to the generator; testing means for testing the quality of the liquid in the passage before it reaches the generator; and means controlled by said testing means for at times preventing the liquid from reaching the generator.

11. In combination, a passage for conducting liquid to a steam generator; means for testing said liquid before it reaches the generator and means associated with said passage and controlled by said testing means for automatically, in accordance with the test of the testing means, diverting liquid from the passage.

12. In combination, a vapor generator; means providing a passage for conducting liquid to the generator; electric circuit-forming means includsaid liquid for completing the circuit; and means controlled by said circuit, as a result of the conductivity of said liquid, for preventing the liquid from reaching the generator.

13. In combination, a supply means; a relay tank; means providing a passage for conducting liquid to a receiver; means for supplying liquid from the supply means to the tank, then to cutoil said supply, and only while the supply is cut off to cause liquid to move from the tank to the receiver; electric circuit forming means including the liquid in the tank for completing the circuit; and means controlled by said circuit when the conductivity is above a predetermined amount for automatically preventing the liquid from the tank from reaching the receiver.

14. In combination, a supply means; a relay tank; means providing a passage for conducting liquid to a receiver; means controlled by liquid in the tank lor alternately connecting said passage and the supply means with the tank for causing liquid from the supply means to flow into the tank and afterwards from the tank toward the receiver; electric circuit forming means in cluding a pair of spaced electrodes in the tank adapted for contact with the liquid for completing the circuit; means associated with said passage and controlled by said circuit when the conductivity is above a predetermined amount for automatically preventing liquid in the passage from reaching the receiver.

15. In combination, a relay tank; means providing a passage for conducting liquid to a receiver; means for alternately causing liquid to flow into the tank and afterwards from the tank to said passage; testing means for testing the liquid in the tank; and means associated with said passage and controlled by said testing means for automatically diverting, in accordance with the test, the liquid from the passage before the liquid reaches the receiver.

16. In combination, a supply means; a relay tank suitable for testing liquid in the tank; a receiver; means providing a passage for conducting liquid to the receiver; and means including a two-way valve controlled by liquid in the tank and associated with said passage for periodically alternately connecting said supply means and passage with tank for causing liquid from the supply means to flow into the tank and afterwards from the tank toward the generator.

17. In combination, a supply means; a relay tank suitable for testing liquid in the tank; means providing a passage for conducting liquid to a receiver; a float adapted to rise and fall in the tank; means including a two-way valve controlled by the fioat and associated with said passage for connecting said supply means with the tank when the float reaches its lower limit and said tank with the passage when the float reaches its upper limit for causing the liquid to flow into the tank and afterwards from the tank toward the receiver; and means in the passage to the receiver for controlling the flow of liquid to the receiver.

18. In combination, a supply means; a relay tank; means providing a passage for conducting liquid to a receiver; a float adapted to rise and fall in the tank; a servo motor controlled by said float, means including a two-Way valve controlled by the servo motor and associated with said passage for periodically alternately connecting said supply means and passage with tank for causing liquid from the supply means to flow into the tank and afterwards from the tank toward the receiver; means for testing the liquid in the tank to determine if it is undesirable; and means interposed in the passage to the receiver and controlled by said testing means for automatically preventing the undesirable liquid in said passage from reaching generator receiver.

19, In combination, a supply means; a relay tank; means providing a passage for conducting liquid to a receiver; means for alternately connecting said supply means and passage with the tank for causing liquid from the supply means to fioW into the tank and afterwards from the tank toward the receiver; means for testing the liquid in the tank; and means including a two-way valve interposed in the passage to the receiver and controlled by said testing means in accordance with the test for automatically diverting liquid from said passage before it reaches the receiver.

20. In combination, a relay tank; means providing a passage for conducting liquid from the tank to a receiver; electric circuit forming means including a pair of spaced electrodes in the tank adapted for contact with the liquid for completing the circuit; a servo-motor controlled by said circuit when the conductivity is a predetermined amount; and means including a two-way valve interposed in the passage to the receiver and controlled by said servo motor, when said conductivity reaches said amount, for automatically diverting liquid from said passage before it reaches the receiver.

21. In combination, a closed tank suitable for testing liquid in the tank; a receiver for liquid under pressure; means providing a passage for conducting liquid from the tank to the receiver; and means communicating with the tank and receiver for furnishing pressure upon the tankliquid when the liquid flows from the tank to the receiver.

22. In combination, a relay tank; a receiver for liquid under pressure; means providing passages for conducting liquid into the tank and from the tank to the receiver; testing means for liquid in the tank; means interposed in the passage to the receiver and controlled by said testing means, in accordance with the test, for at times automatically preventing the liquid from reaching the receiver; and means controlled by the testing means communicating with the tank and receiver for furnishing pressure upon the tank-liquid when the liquid flows from the tank to the receiver.

23. In combination, a relay tank; a receiver for liquid under pressure; means providing a passage for conducting liquid from the tank to the receiver; electric circuit-forming means including a pair of spaced electrodes in the tank adapted for contact with the liquid; means interposed in the passage to the receiver and controlled by said circuit, when the conductivity of the liquid reaches a predetermined amount, for automatically diverting the liquid from said passage before reaching the receiver; and means for exerting pressure upon the tank-liquid when the liquid flows from the tank,

24. In combination, a main passage for conducting liquid; a branch passage communicating with the main passage; means for testing the quality of the liquid in the main passage; and means associated with said passage and controlled by said testing means for automatically, in accordance with. said testing, diverting liquid from the main passage to'the branch passage, while the liquid is flowing into the passage, thereby eliminating the diverted liquid from the passage and preventing the liquid from passing through the end of the main passage while still allowi liquid to enter into the main 25. In combination, a receiver; means providing a passage for conducting liquid to the receiver; electric circuit forming means including said liquid, while being conducted, for completing the circuit; and means controlled by said circuit for automatically diverting liquid from the passage, before it reaches the receiver, whenever the current in the circuit is equal to a predetermined amount.

26. In combination with a source of liquid and an intermediate tank, a path for conducting liquid to said tank; a collecting tank; a second path for conducting liquid from the intermediate tank to said collecting tank; an electric circuit including testing electrodes in contact with said liquid in the intermediate tank; and means controlled by said circuit in accordance with the conductivity of the liquid to control the flow, through said second path, independently of the flow in the first path, of the liquid which has been tested in the intermediate tank.

27. In combination, a supply means; a relay tank; means providing a passage for conducting liquid to a receiver; means for supplying liquid from the supply means to the tank, then to cutoff said supply, and only while the supply is cut off to cause liquid to move from the through said passage to the receiver; testing means for testing the conductivity of the liquid in the tank; and means controlled by said testing means when the conductivity equals a predetermined amount for automatically preventing the liquid from the tank from reaching the receiver.

28. In a testing apparatus, the combination of a supply means; arelay tank suitable for holding liquid for taking a receiver; means providing a passage for conducting liquid to the receiver; and means including a two-way valve controlled by liquid in the tank and associated with said passages for periodicallv alternately connecting said supply means and passage with j tank for causing liquid from the supply means to flow into the tank and afterwards from the tank toward the receiver.

29. In a testing apparatus, the combination of closed tank suitable for liquid testing; a r 1 supply evaporator;

ing the direction of the liquid one way or another when the res stivity of such liquid increases beyond or decreases under a predetermined amount.

31. In combination, a relay tank; means providing a passage for conducting liquid to a selecting device; means for causing liquid to flow into the tank and afterwards from the tank to said passage; electric circuit forming means including the liquid in the tank for completing a circuit; and means controlled by said ccuit for automatically directing the liquid to one or another direction of the selecting device when the current of the circuit reaches a predetermined amount.

32. In combination, a passage for conducting liquid; electric circuit forming means including said liquid for completing the circuit; and means controlled by circuit for automatically changing the direction of the liquid from one direction to another direction when the resistivity of the liquid changes to a predetermined value.

33.111 combination, a steam boiler; a liquid supply for supplying liquid of variable conductivity which is harmful to the boiler at a conductivity of one value and substantially harmless at anothe" conductivity; means providing a passage for conducting said liquid from the supply to said boiler; electric circuit-forming means including said liquid between the supply and boiler for completing the circuit; and means controlled by said circuit and set in operation by the liquid when at the harmful conductivity of said value for preventing the harmful liquid from reaching the boiler, thereby preventing damage to the boiler.

A method of protecting a vapor generator using liquid of variable conductivity which is harmful to the generator at one value or" conductivity and suiiiciently harmless for use at another conductivity, said method comprising conducting the liquid from the supply to the genera-- tor; passing electric current through the liquid between the supply and generator, whereby the current is varied if said conductivity is varied; and automatically causing said current to operate to prevent said liquid from reaching the generator when the conductivity varies to the harmful value, thereby preventing damage to the boiler.

35. In combination, an evaporator; a liquid supply for supplying liquid of variable quality which is harmful to the evaporator at a quality of one value and substantially harmless at another quality; means providing a passage for said liquid from the supply to said evaporator; testing means for testing said liquid between the nd means controlled by said testing means and set in operation by the liquid. when at the harmful value for preventing the harmful liquid from reaching and damaging the boiler.

36. A method of protecting a vapor generator using liquid of variable quality which is harmful to the generator at one value and sufficiently h rmless for use when at another quality, said method. comprising conducting the liquid from the supply to the generator while harmless; testing the liquid between the supply and generator, whereby the test-result is varied if said quality is varied; and automatically causing said test result to operate to prevent said liquid from reaching and damaging the generator when the quality varies to said harmful value.

37. In combination, a relay tank; testing means for testing the liquid in the tank; means providing a passage for conducting liquid to a receiver; means operative independently of the action of the testing means for alternately causing liquid to flow into the tank and afterwards to flow from the tank to said passage and thence to the receiver; and means associated with said passage and controfled by said testing means, in accordance with the test, for automatically diverting the flowing liquid from the passage before the liquid reaches the receiver.

38. In combination, a relay tank; a receiver for liquid under pressure; means providing passages for conducting liquid into the tank and from the tank to the receiver; testing means for the tank; means interposed in the passage to the receiver and controlled by said testing means for at times automatically preventing the liquid from reaching the receiver; and means controlled by the testing means communicating with the tank and receiver for furnishing pressure upon the tankliquid when the liquid flows from the tank to the receiver, and holding the pressure from the tank liquid when liquid flows into the tank.

39. In combination, a supply means; a relay tank; means providing a passage for conducting liquid to a receiver; means for supplying liquid from supply means to the tank, then to cutoff said supply, and only while the supply is cut off to cause liquid to move from the tank through said passage to the receiver; testing means for testing the conductivity of the liquid in the tank; means controlled by said testing means when the conductivity equals a predetermined amount for automatically diverting the liquid from said passage for preventing the liquid from the tank from reaching the receiver.

40. In combination, a supply means; a testing compartment; means providing a passage for conducting liquid to a receiver; means for supplying liquid from the supply means to said compartment, then to cut-off said supply, and only while the supply is cut off to cause liquid to move from the compartment through said passage to the receiver; testing means for testing the conductivity of the liquid in the compartment; and means controlled by said testing means when the conductivity of the liquid equals a predetermined amount for automatically diverting such liquid from the passage for preventing the such liquid from reaching the receiver while allowing liquid to leave said compartment to prepare the compartment to receive liquid from the supply means.

411. In combination, a supply means; means providing a passage for conducting liquid to a receiver; testing means for testing the conductivity of the liquid supplied to said passage; control means for supplying liquid from the supply means to the passage and testing means, then to cut-oil said supply means from the passage, and only while the supply means is thus cut off to cause liquid to move from the passage toward the receiver; and means controlled by said testing means when the conductivity of the liquid equals a predetermined amount for automatically diverting such liquid from the passage at a point between the testing means and the receiver, thereby preventing such liquid from reaching the receiver, the cutting oil of said control means from the passage preventing the mixing of the tested liquid from the passage with a new portion of liquid to be tested.

42. In combination, a closed tank; a receiver for liquid under pressure; means providing a passage for conducting liquid from the tank to the receiver; testing means in the tank, for contacting liquid therein for testing the liquid; control means for causing liquid to flow into the bottom of the tank and to rise into contact with the testing means for testing the liquid, and then to flow downwardly from said tank and testing means through said passage to the receiver after testing; and means communicating with the tank and receiver for furnishing downward pressure upon the liquid in the tank when the liquid flows from the tank and testing means to the receiver, thereby facilitating the downward flow of the liquid from the testing means.

43. In a liquid testing apparatus, the combination of a closed tank adapted for testing liquid and adapted to receive testing means for contacting liquid therein for testing the liquid; a receiver for liquid under pressure; means providing a passage for conducting liquid from the tank to the receiver; means for causing liquid to flow into the tank into contact with testing means for testing, and then to flow from said tank through said passage to the receiver after testing; and means communicating with the tank and receiver for furnishing pressure upon the liquid in the tank when the liquid flows from the tank to the receiver, thereby facilitating the flow of the liquid from the testing means.

MARIUS SAINTE-MARTINE. 

